Refer to the Treatments Listed Below to Answer the Following

question 11

Multiple Choice

Refer to the treatments listed below to answer the following questions.
You isolate an infectious substance that is capable of causing disease in plants, but you do not know whether the infectious agent is a bacterium, virus, viroid, or prion. You have four methods at your disposal that you can use to analyze the substance in order to determine the nature of the infectious agent.
I. treating the substance with nucleases that destroy all nucleic acids
and then determining whether it is still infectious
II. filtering the substance to remove all elements smaller than what can
be easily seen under a light microscope
III. culturing the substance by itself on nutritive medium, away from
any plant cells
IV. treating the sample with proteases that digest all proteins and then
determining whether it is still infectious
-If you already knew that the infectious agent was either bacterial or viral, which treatment would allow you to distinguish between these two possibilities?

• A) I
• B) II
• C) III
• D) IV
• E) either II or IV

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Definitions:

Deep Ocean

The part of the ocean beyond the continental shelf, characterized by great depths, low temperatures, and high pressure.

Fossil Shells

Remnants of the hard protective outer layer of once-living aquatic organisms, which have been preserved in the Earth's crust over geological time.

Dry Climate

A type of climate characterized by low precipitation levels, leading to desert landscapes and sparse vegetation.

Isotopes

Variations of a chemical element that have the same number of protons but different numbers of neutrons in their nuclei.